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diff --git a/js/src/scrollspy.js b/js/src/scrollspy.js
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+/**
+ * --------------------------------------------------------------------------
+ * Bootstrap (v5.2.3): scrollspy.js
+ * Licensed under MIT (https://github.com/twbs/bootstrap/blob/main/LICENSE)
+ * --------------------------------------------------------------------------
+ */
+
+import { defineJQueryPlugin, getElement, isDisabled, isVisible } from './util/index'
+import EventHandler from './dom/event-handler'
+import SelectorEngine from './dom/selector-engine'
+import BaseComponent from './base-component'
+
+/**
+ * Constants
+ */
+
+const NAME = 'scrollspy'
+const DATA_KEY = 'bs.scrollspy'
+const EVENT_KEY = `.${DATA_KEY}`
+const DATA_API_KEY = '.data-api'
+
+const EVENT_ACTIVATE = `activate${EVENT_KEY}`
+const EVENT_CLICK = `click${EVENT_KEY}`
+const EVENT_LOAD_DATA_API = `load${EVENT_KEY}${DATA_API_KEY}`
+
+const CLASS_NAME_DROPDOWN_ITEM = 'dropdown-item'
+const CLASS_NAME_ACTIVE = 'active'
+
+const SELECTOR_DATA_SPY = '[data-bs-spy="scroll"]'
+const SELECTOR_TARGET_LINKS = '[href]'
+const SELECTOR_NAV_LIST_GROUP = '.nav, .list-group'
+const SELECTOR_NAV_LINKS = '.nav-link'
+const SELECTOR_NAV_ITEMS = '.nav-item'
+const SELECTOR_LIST_ITEMS = '.list-group-item'
+const SELECTOR_LINK_ITEMS = `${SELECTOR_NAV_LINKS}, ${SELECTOR_NAV_ITEMS} > ${SELECTOR_NAV_LINKS}, ${SELECTOR_LIST_ITEMS}`
+const SELECTOR_DROPDOWN = '.dropdown'
+const SELECTOR_DROPDOWN_TOGGLE = '.dropdown-toggle'
+
+const Default = {
+  offset: null, // TODO: v6 @deprecated, keep it for backwards compatibility reasons
+  rootMargin: '0px 0px -25%',
+  smoothScroll: false,
+  target: null,
+  threshold: [0.1, 0.5, 1]
+}
+
+const DefaultType = {
+  offset: '(number|null)', // TODO v6 @deprecated, keep it for backwards compatibility reasons
+  rootMargin: 'string',
+  smoothScroll: 'boolean',
+  target: 'element',
+  threshold: 'array'
+}
+
+/**
+ * Class definition
+ */
+
+class ScrollSpy extends BaseComponent {
+  constructor(element, config) {
+    super(element, config)
+
+    // this._element is the observablesContainer and config.target the menu links wrapper
+    this._targetLinks = new Map()
+    this._observableSections = new Map()
+    this._rootElement = getComputedStyle(this._element).overflowY === 'visible' ? null : this._element
+    this._activeTarget = null
+    this._observer = null
+    this._previousScrollData = {
+      visibleEntryTop: 0,
+      parentScrollTop: 0
+    }
+    this.refresh() // initialize
+  }
+
+  // Getters
+  static get Default() {
+    return Default
+  }
+
+  static get DefaultType() {
+    return DefaultType
+  }
+
+  static get NAME() {
+    return NAME
+  }
+
+  // Public
+  refresh() {
+    this._initializeTargetsAndObservables()
+    this._maybeEnableSmoothScroll()
+
+    if (this._observer) {
+      this._observer.disconnect()
+    } else {
+      this._observer = this._getNewObserver()
+    }
+
+    for (const section of this._observableSections.values()) {
+      this._observer.observe(section)
+    }
+  }
+
+  dispose() {
+    this._observer.disconnect()
+    super.dispose()
+  }
+
+  // Private
+  _configAfterMerge(config) {
+    // TODO: on v6 target should be given explicitly & remove the {target: 'ss-target'} case
+    config.target = getElement(config.target) || document.body
+
+    // TODO: v6 Only for backwards compatibility reasons. Use rootMargin only
+    config.rootMargin = config.offset ? `${config.offset}px 0px -30%` : config.rootMargin
+
+    if (typeof config.threshold === 'string') {
+      config.threshold = config.threshold.split(',').map(value => Number.parseFloat(value))
+    }
+
+    return config
+  }
+
+  _maybeEnableSmoothScroll() {
+    if (!this._config.smoothScroll) {
+      return
+    }
+
+    // unregister any previous listeners
+    EventHandler.off(this._config.target, EVENT_CLICK)
+
+    EventHandler.on(this._config.target, EVENT_CLICK, SELECTOR_TARGET_LINKS, event => {
+      const observableSection = this._observableSections.get(event.target.hash)
+      if (observableSection) {
+        event.preventDefault()
+        const root = this._rootElement || window
+        const height = observableSection.offsetTop - this._element.offsetTop
+        if (root.scrollTo) {
+          root.scrollTo({ top: height, behavior: 'smooth' })
+          return
+        }
+
+        // Chrome 60 doesn't support `scrollTo`
+        root.scrollTop = height
+      }
+    })
+  }
+
+  _getNewObserver() {
+    const options = {
+      root: this._rootElement,
+      threshold: this._config.threshold,
+      rootMargin: this._config.rootMargin
+    }
+
+    return new IntersectionObserver(entries => this._observerCallback(entries), options)
+  }
+
+  // The logic of selection
+  _observerCallback(entries) {
+    const targetElement = entry => this._targetLinks.get(`#${entry.target.id}`)
+    const activate = entry => {
+      this._previousScrollData.visibleEntryTop = entry.target.offsetTop
+      this._process(targetElement(entry))
+    }
+
+    const parentScrollTop = (this._rootElement || document.documentElement).scrollTop
+    const userScrollsDown = parentScrollTop >= this._previousScrollData.parentScrollTop
+    this._previousScrollData.parentScrollTop = parentScrollTop
+
+    for (const entry of entries) {
+      if (!entry.isIntersecting) {
+        this._activeTarget = null
+        this._clearActiveClass(targetElement(entry))
+
+        continue
+      }
+
+      const entryIsLowerThanPrevious = entry.target.offsetTop >= this._previousScrollData.visibleEntryTop
+      // if we are scrolling down, pick the bigger offsetTop
+      if (userScrollsDown && entryIsLowerThanPrevious) {
+        activate(entry)
+        // if parent isn't scrolled, let's keep the first visible item, breaking the iteration
+        if (!parentScrollTop) {
+          return
+        }
+
+        continue
+      }
+
+      // if we are scrolling up, pick the smallest offsetTop
+      if (!userScrollsDown && !entryIsLowerThanPrevious) {
+        activate(entry)
+      }
+    }
+  }
+
+  _initializeTargetsAndObservables() {
+    this._targetLinks = new Map()
+    this._observableSections = new Map()
+
+    const targetLinks = SelectorEngine.find(SELECTOR_TARGET_LINKS, this._config.target)
+
+    for (const anchor of targetLinks) {
+      // ensure that the anchor has an id and is not disabled
+      if (!anchor.hash || isDisabled(anchor)) {
+        continue
+      }
+
+      const observableSection = SelectorEngine.findOne(anchor.hash, this._element)
+
+      // ensure that the observableSection exists & is visible
+      if (isVisible(observableSection)) {
+        this._targetLinks.set(anchor.hash, anchor)
+        this._observableSections.set(anchor.hash, observableSection)
+      }
+    }
+  }
+
+  _process(target) {
+    if (this._activeTarget === target) {
+      return
+    }
+
+    this._clearActiveClass(this._config.target)
+    this._activeTarget = target
+    target.classList.add(CLASS_NAME_ACTIVE)
+    this._activateParents(target)
+
+    EventHandler.trigger(this._element, EVENT_ACTIVATE, { relatedTarget: target })
+  }
+
+  _activateParents(target) {
+    // Activate dropdown parents
+    if (target.classList.contains(CLASS_NAME_DROPDOWN_ITEM)) {
+      SelectorEngine.findOne(SELECTOR_DROPDOWN_TOGGLE, target.closest(SELECTOR_DROPDOWN))
+        .classList.add(CLASS_NAME_ACTIVE)
+      return
+    }
+
+    for (const listGroup of SelectorEngine.parents(target, SELECTOR_NAV_LIST_GROUP)) {
+      // Set triggered links parents as active
+      // With both <ul> and <nav> markup a parent is the previous sibling of any nav ancestor
+      for (const item of SelectorEngine.prev(listGroup, SELECTOR_LINK_ITEMS)) {
+        item.classList.add(CLASS_NAME_ACTIVE)
+      }
+    }
+  }
+
+  _clearActiveClass(parent) {
+    parent.classList.remove(CLASS_NAME_ACTIVE)
+
+    const activeNodes = SelectorEngine.find(`${SELECTOR_TARGET_LINKS}.${CLASS_NAME_ACTIVE}`, parent)
+    for (const node of activeNodes) {
+      node.classList.remove(CLASS_NAME_ACTIVE)
+    }
+  }
+
+  // Static
+  static jQueryInterface(config) {
+    return this.each(function () {
+      const data = ScrollSpy.getOrCreateInstance(this, config)
+
+      if (typeof config !== 'string') {
+        return
+      }
+
+      if (data[config] === undefined || config.startsWith('_') || config === 'constructor') {
+        throw new TypeError(`No method named "${config}"`)
+      }
+
+      data[config]()
+    })
+  }
+}
+
+/**
+ * Data API implementation
+ */
+
+EventHandler.on(window, EVENT_LOAD_DATA_API, () => {
+  for (const spy of SelectorEngine.find(SELECTOR_DATA_SPY)) {
+    ScrollSpy.getOrCreateInstance(spy)
+  }
+})
+
+/**
+ * jQuery
+ */
+
+defineJQueryPlugin(ScrollSpy)
+
+export default ScrollSpy